This invention relates to fitments for bulk containers and, more particularly, to a push/turn tap and drain spout fitment assembly for gravity discharge of bag-in-box bulk containers, wherein a fitment is connected to a plastic bag or liner supported within a multi-wall fibreboard sleeve of a bulk container intended for use as a heavy-duty shipping container for liquids or dry flowable products, particularly those that require evacuation of the contained product by gravity flow, and whose structure, size, or weight do not readily allow for tipping on their side to allow for initiation of product flow.
The term "bulk container" as used herein denotes a multi-wall fibreboard shipping container for flowable substances and, more particularly, a heavy-duty shipping container for the bulk transport of flowable bulk materials, including liquids, dry powders or granular substances, semi-solid materials such as grease, pastes or adhesives and, as well, highly viscous fluids, generally contained within a plastic bag or liner supported within the container, in volumes of at least fifty-five gallons (approximately two hundred ten liters) and in quantities of weight greater than four hundred-fifty pounds (approximately two hundred kilograms).
Bag-in-box packaging has been widely accepted as containers for flowables. Such packaging combines the advantages of the retention capabilities of plastic bags or liners with the strength of an outer fibreboard box or sleeve. Requirements for bulk containers having an inner plastic bag or liner are more stringent with respect to drain devices because of the high load and stresses to which the devices, and the joints between the drain devices and the fibreboard container or plastic, or both, will be subjected, as well as the potential for leakage in the event of failure of such components.
Gravity flow spout devices located at the bottom of fibreboard bulk containers for flowables have traditionally been shipped with a discharge valve attached thereto, or provided with a sealing membrane covering the fitment opening that is designed to be pierced or torn by a puncturing device, or, as commonly seen in use with cooling radiators, provided with a threaded drain sealing plug which, when screwed inwardly, expose slots within an outer housing to allow escape of the contained coolant.
Several disadvantages are associated with use of each of the aforementioned gravity drain devices. A shipping container having a valve attached thereto, for example, is costly and also exposes the valve to transit damage and, as well, to tampering. Membrane style fitments, on the other hand, are subject to leakage, particularly when used in connection with shipping containers which carry heavy bulk loads and wherein the membrane will be subject to significant, cyclic forces during transit and static wall stresses as where such containers are stacked. Additionally, there is a chance that pieces or fragments of the membrane material will be forced into the outlet, as the liquid begins to drain, causing either a partial blockage of the outlet or dislodging, and thus contaminating the product being emptied. Radiator style plugs and spouts also disadvantageously protrude well beyond the plane of the outer surface of the container and are thus subject to transit damage. In addition, radiator style plugs and spouts are subject to tampering, and are cumbersome to use with certain types of containers, particularly containers used in conjunction with flexible liner bags, in which case the drain spout fitment must be attached and sealed to the liner bag prior to filling. Additionally, radiator type plugs tend to allow for a limited cross-sectional flow area, thus restricting the flow, and this is particularly disadvantageous with respect to withdrawal of viscous products from a container.